Improvement in steam-boilers



UNITED STATES PATENT OFFICE.

SAMUEL STEINllIETZ, OF CHICAGO, ILLINOIS, ASSIGNOR TO ANDRE RIERSEN, OF SAME PLACE.

IMPROVEMENT IN STEAM-BOILERS.

Specification forming part of Letters Patent No. 37,795, dated February 24, 1863.

To all whom it may concern:

Be it known that I, SAMUEL STEINMETZ, of Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Steam-Boilers; and I do hereby declare the following to be a full and exact description of the same, reference being had to the accompanying drawings, making part of this specification, in which- Figure l is a side elevation of a portion of a steam boiler illustrating my invention. Fig. 2 is a similar view, representing the yielding head elevated from its seat, a portion of the cupola being broken away to expose the interior. Fig. 3 is a plan of the same in its closed position.

Similar letters of reference indicate corresponding parts in the several views.

The object of my invention is to prevent the explosion of steam-boilers owing to excessive pressure from any cause. The device commonly called a safety-valve, which is applied to steam-boilers to equalize the press ure by permitting a gradual escape of steam when the pressure rises above any point at which the valve may be set, is entirely ineffectual to prevent the disastrous effects resulting from a large and sudden increase of pressure from accidental eailses. This is sufficiently proved by the well-known fact that explosions are of frequent occurrence, notwithstanding the so-called safety-valve is in universal use. 4

In order to prevent the possibility of explosion by increase of steam-pressure, however great or sudden such increase may be, my invention consists in constructing a steamboiler with a certain known portion of its shell or exterior more yielding than the remainder, such yielding portion being of sufficient area to carry off any excessive pressure which can possibly arise, and being, moreover, under such control as'to prevent any disastrous consequences resulting from an explosion.

To enable others skilled in the art to which my invention appertains to fully understand and use the same, I will proceed to describe its nature and operation.

A may represent a steamboiler of any form.

Bis acupola or steam-drum,forming a steamchamber in the upper part of the boiler. The

said cupola is formed with a seat, 0, in which rests a yielding head, D, constituting a valve of large area. This yielding head is secured against displacement by wings E, extending from its lower surface down into the cupola, and by a guiderod, F, projecting from its upper surface and working through a yoke, G.

H is a spiral spring, encircling the rod F between the yoke G and head D, and exerting a downward pressure upon the latter.

I I I I are a series of levers, fulcrumed at one end to standards J J J J and at their other ends held down by hooks K K K K which hooks are held at their lower ends by springs l in cylinders L. The efi'ect of this device is to hold the hooks down with considerable force, but permit them a limited vertical play. The said hooks work through guides M M M M, within which they have a slight horizontal play in a direction parallel with the levers I l I I.

k k k k are inclined projections on the inner edges or faces of the hooks, which projections bearing against the guides throw the hooks outward, so as to detach them from the end of the levers and release the latter when the hooks are drawn upward, as hereinafter explained. The posts N, projecting from the levers I I I I, bear upon the yielding head D, so as to hold it forcibly down so long as the levers are retained by the hooks, as shown in Fig. 1.

V represents an ordinary safety-valve.

The operation is as follows: The safety-valve V will perform its customary function of permitting a gradual escape of steam in order to carry off excessive pressure arising from ordinary circumstances. So long as the boiler continues to work as intended, the yielding head remains closed and inactive, but in the event of a sudden increase of p1 essure from any accidental cause, which with a boiler of common construction would resultin its explosion and destruction, the head D, being the most yielding part, will rise from its seat, and the hooks K K? K K being, by the action of the inclined projections 70 k k In, thrown off the ends of the levers, the latter release the head, which rises and permits a free escape of steam. This position of the parts is shown in Fig. 2. The excessive pressul ebeingthus carried off, the yielding head is again forceddown leased when raised from its seat, and thus prevent disastrous consequences from an explosion.

2. The combination of the yielding head D, levers I I I I, springhooks J J J 'J*, and return ing-spring H, all constructed, arranged, and operating substantially as herein shown and described.

SAMUEL STEINMETZ.

Witnesses JULIUS ROSENTHAL, WILLIAM ESOHENBURG. 

